Among the healthy snacks Ms McCartney recommends are corn on the cob, plenty of salad on sandwiches to fill them up, roast vegetables with yoghurt dipping sauce are some vegetable options.

Lean meat wraps, sushi, homemade muffins and soups in a flask are some of the heartier lunch options. For dairy products, Ms McCartney suggests tubs of yoghurt or custard, a carton of milk or reduced fat cubed cheese or cheese sticks or a hard-boiled egg.

Ipswich Girls' Grammar School prep teacher Tanya Barney said it was common to find carrots and celery with dips in the children's lunchboxes.

"I find that a lot of my parents are good at giving them healthy alternatives," she said.